In the prior art, the use of steam generators to sterilize articles for medical procedures and the like is well known. One type of steam generator for sterilization of articles is disclosed in U.S. Pat. Nos. 5,271,893 and 5,290,511 to Newman, herein incorporated in their entirety by reference herein. In these patents, a boiler operates as a flash boiler wherein water supplied to the boiler is immediately evaporated so that the boiler stays essentially dry during steam generation. The temperature of the boiler is monitored using a temperature sensor placed inside the boiler, whereby evaporation of the water is signified by a sharp increase in the boiler temperature. Water is injected into the boiler at this time to generate additional steam, and the process is repeated continually to supply steam while keeping the boiler in a dry state. The water is injected using a dosing pump and a conduit having an end positioned near the bottom of the chamber of the boiler. The thus-generated steam exits the boiler in another conduit and enters a sterilizing cassette.
While these steam-on-demand boilers offer significant advantages over other types of steam generators, the boilers are made of aluminum, which is cast around its heating coils. The aluminum material tends to oxidize over time. The oxides can coat the temperature sensor and affect its performance. Moreover, steam generation output is sensitive to the manner in which the water is injected into the boiler chamber and placement of the temperature sensor, and steam output can sometimes suffer due to improper water injection and sensor placement.
Therefore, a need exists to improve the generation of steam using steam-on-demand generators. In response to this need, the present invention provides an improved steam-on-demand generator that has improved corrosion resistance, and better steam generation capability.